SLR recommendations:
most versatile: Hasselblad 500 C/M (interchable backs and viewfinders, huge range of lenses, relatively compact, and there aredigital backs available.
For tripod use mostly (because of weight and size): Mamiya RZ67 II. Like the Hasselblad it has interchangable back, viewfinders, and a large rangeof excellent lenses.-
Primarily for landscape and outdoor work: Pentax 67 II. Its shaped like 35mm SLR and has a small range of interchangable viewfinders. The lenses are superb at asgood if not better than the Zeiss lenses used by Hasselblad. The one downside is tjat if you use electronic flash the maximum shutter-sync speed is 1/30.
(Pentax 67 trivia: the first two photographers in tje USA to own and shoot with the Pentax 67 were Hiro and Diane Arbus.)
Twin Lens Reflex:
Rollei or Mamiya. The Rollei bodies are smaller than the Mamiya TLRs but lack the Mamiya's capability to switch between a wide, normal, and short telephoto lens.
Rangefinders:
Fuji made both small 6x4.5 rangefinders tjat are reallynicebut Inever liked the 6x4.5 format, and also some great 6x7cm, 6x9cm rangefinder cameras, andalso the G617 series of 6x17cm panoramic cameras.
of you don'talways working froma tripod and shoot architecture, landscapes and still life consider a medium format view camera: either the Arca-Swiss 69FC or Linhof TK69, although every 4x5 view camera I ever used also took medium format backs..
Ellis Vener
Free your eyes and the rest will follow. (With apologies to George Clinton.)